- Judicial Estoppel Is Equitable Doctrine Against Party Benefiting From Inconsistent Positions: “It may be laid down as a general proposition that, where a party assumes a certain position in a legal proceeding, and succeeds in maintaining that position, he may not thereafter, simply because his interests have changed, assume a contrary position, especially if it be to the prejudice of the party who has acquiesced in the position formerly taken by him.” Davis (U.S. 03/04/1895). Non-exhaustive list of factors for this equitable doctrine of “judicial estoppel”: “several factors typically inform the decision whether to apply the doctrine in a particular case: First, a party’s later position must be “clearly inconsistent” with its earlier position. Second, courts regularly inquire whether the party has succeeded in persuading a court to accept that party’s earlier position, so that judicial acceptance of an inconsistent position in a later proceeding would create “the perception that either the first or the second court was misled,” Absent success in a prior proceeding, a party’s later inconsistent position introduces no “risk of inconsistent court determinations,” and thus poses little threat to judicial integrity. A third consideration is whether the party seeking to assert an inconsistent position would derive an unfair advantage or impose an unfair detriment on the opposing party if not estopped.” New Hampshire (U.S. 05/29/2001). See Columbia Sportswear (Fed. Cir. 09/15/23) (declining, as matter of equity, to apply judicial estoppel against patentee based on positions it took in support of obtaining a since-vacated damages verdict); Egenera (Fed. Cir. 08/28/20) (rev’g that judicial estoppel blocks adding back an inventor patentee had removed in USPTO; not “clearly inconsistent” because intervening claim construction changed who qualified as inventor; § 256 petition not “persuasion” of an agency acting as a “court”); Minnesota Mining (Fed. Cir. 08/30/02) (applying regional circuit law, judicial estoppel blocks party on appeal arguing that verdict was internally inconsistent when successfully refuted that contention in trial court); Alexsam (Fed. Cir. 03/03/22) (non-precedential) (rev’g Summ. J. judicial estoppel because patent owner’s positions in PTAB and in district court re effect of covenant not to sue were consistent); Wilson (Fed. Cir. 10/21/19) (non-precedential) (aff’g no judicial estoppel against interference party asserting that a prior art reference discloses a claim element because not clearly inconsistent with arguments by that party’s real party in interest, prosecuting another application, distinguishing that reference, and context and record in two proceedings “markedly different”); Interdigital (Fed. Cir. 11/03/17) (non-precedential) (no judicial estoppel from patent owner’s statement in prior litigation that claim element corresponded to single embodiment in Spec., because patent owner lost that prior litigation.) “The doctrine also applies to administrative proceedings in which a party obtains a favorable order by making an argument that it seeks to repudiate in a subsequent judicial proceeding.” Lampi (Fed. Cir. 09/28/00) (applying regional circuit law). “A party may be judicially estopped from asserting clearly inconsistent positions on claim construction.” Transclean (Fed. Cir. 01/18/07) (party judicially estopped to deny privity). Federal Circuit applies regional circuit law where estoppel based on statements made in district court but Federal Circuit law where based on statements made Patent Office. Sherwin-Williams (Fed. Cir. 07/25/24) (non-precedential) (aff’g judicial estoppel barred patent owner from denying that prior art reference disclosed certain feature (BPA-free coating) where patent owner had successfully defended a reexamination proceeding based on persuading Board that the reference disclosed that feature, despite Board decision later being vacated for lack of continuing controversy).